Chemical materials and additives needed for the production of glass
Production process of 1.3.1 glass1. Raw material pretreatment. The bulk raw materials (quartz sand, soda ash, limestone, feldspar, etc.) grinding, so that dry wet raw materialsDry, iron containing raw materials for iron removal, in order to ensure the quality of glass.2, batch preparation. According to the product, the composition of the mixture is slightly different. For example, ordinary float glass batch (calculated in accordance with 1 weight boxes of 50 kilograms), need to consume 33.55 kg of quartz sand, limestone, dolomite, 2.96 kg 8.57 kg 11.39 kg of soda, Glauber's salt 0.55 kg, 3.45 kg, 0.03 kg of feldspar powder etc..3, melting. The glass mixture is heated in a bath or crucible furnace at a high temperature (1550-1600 degrees) to form a liquid glass that is uniform, free of bubbles and conforms to the molding requirements.
1. Blending of raw materials. The main ingredients of float glass are: 73% of silica, 13% of sodium carbonate, 9% of calcium oxide and 4% of magnesium. The ingredients are mixed in proportion, followed by the addition of small pieces of recycled glass.2. Melting of raw materials. The prepared material passes through a mixing bin and then goes into a kiln with 5 chambers and is heated at about 1550 degrees centigrade to become a molten glass. 3. Glass forming. Molten glass flows into a tin bath and floats over molten molten tin, at a temperature of about 1000 degrees celsius. The molten glass on the tin solution forms a glass band of 3.66 meters wide and a thickness of 3mm to 19mm. Because the glass and the tin are very different in viscosity, the molten glass at the top does not mix with the molten tin below, and forms very smooth contact surfaces.4. Cooling of molten glass. When the glass band leaves the bath, the temperature is about 600 degrees Celsius, then it enters the annealing chamber or the continuous cooling kiln, and the temperature of the glass is gradually reduced to 50 degrees celsius. Thus, the glass produced by the Xu cooling method is also called annealed glass. 5, cutting and storage. After the cold, the glass passes through several stages of quality inspection, then cut into different sizes for packaging, storage, storage or transportation.Quartz sand is a hard, abrasion resistant and stable chemical silicate mineral. Its main mineral composition is SiO2, the color of quartz sandFor the white, colorless or translucent, 7 hardness, brittle cleavage, conchatus fracture, oil sheen, density 2.65, bulk density (1-2.0 = 1.6), 20-200 was 1.5, the chemical, thermal and mechanical properties have obvious anisotropy, insoluble in acid, slightly soluble in KOH solution, the melting point of 1750 DEG C.
The production process of float glass is introduced by taking ordinary production line of daily melting capacity of 600 tons in China as an example.Float glass is made in tin bath. The length of the whole production line is about 500 meters. It can produce 550 to 600 tons of glass every day. It is equivalent to 3 meters wide, 3 millimeters thick, and the glass belt is about 25 kilometers in length. Once started, 24 hours a day is uninterrupted until the furnace is stopped for about 8-10 years. Float production is the main mode of production of flat glass
